diff --git a/tw88xx_util.py b/tw88xx_util.py
index 6a679b2..12cef76 100644
--- a/tw88xx_util.py
+++ b/tw88xx_util.py
@@ -18,6 +18,11 @@ parser.add_argument('-j', '--jlink',
                     help='J-Link (serial) to use for SWD',
                     default=None
                     )
+parser.add_argument('-b', '--bus',
+                    help='/dev/i2c bus number',
+                    type=int
+                    default=1
+                    )
 parser.add_argument('-t', '--type',
                     help='TX88xx type',
                     choices=('tw8836'),
@@ -29,6 +34,10 @@ args = parser.parse_args()
 if args.interface == 'swd':
     from i2c_interfaces import JLinkSwdI2CInterface
     i2c = JLinkSwdI2CInterface(jlink_serial=args.jlink)
+elif args.interface == 'dev':
+    from i2c_interfaces import DevI2CInterface
+    i2c = DevI2CInterface(bus=args.bus)
+
 
 i2c.open()
 if args.type == 'tw8836':
@@ -45,9 +54,10 @@ if args.command == 'get_id':
 elif args.command == 'dump_flash':
     # tw88xx.prepare_flash_read(cmd=[0x03, 0x1a, 0x9d, 0x84], read_len=8)
     tw88xx.execute_flash_cmd(cmd=[0xE9], read_len=0)
-    data=[]
-    for block_start in range(0x1a9d84,0x1a9d84+480*480,8):
-        block = tw88xx.execute_flash_cmd(cmd=[0x03, (block_start>>16) & 0xFF, (block_start>>8) & 0xFF, block_start& 0xFF], read_len=8, data=[0x5a]*8)
+    data = []
+    for block_start in range(0x1a9d84, 0x1a9d84+480*480, 8):
+        block = tw88xx.execute_flash_cmd(cmd=[0x03, (block_start >> 16) & 0xFF,
+                                         (block_start >> 8) & 0xFF, block_start & 0xFF], read_len=8, data=[0x5a]*8)
         data.extend(block)
         print(f'{block_start:06x}: {block.hex()}')